Dado saw



Nov. 25, 1930. w. B. HUTHER 1,732,507

DADO SAW Filed Sept. 13, 1927 2 Sheets-Sheet l is ATTO NEYS Nov. 25,1930. w. B. HUTHER 1,782,507

DADO SAW Filed Sept. 13 1927 2 Sheets-Sheet 2 llllllifili lilllllu-xINVENTOR ATTQRN EYS Patented Nov., 25, I930 nmfiurllerumfie density, oreasement, newton, A ooitroRAmdN 'oF YORK mpg ifiinitatitn' he se telntl-13, retest-1 4,1 Ne. 215312.

Thepresht invention relates to sh called dadofvvohhle or groovmgsaWs,"and has 101' an object-the produetion or a saw ofthis type Whiehis stronger, more durable and 1 niore e'flieifnt inoperatio'n than thegrooving saws heretofore constructed; A further objeet is to simplifythe manufacture of saws of thisty'pe. A further object is the provisionwith straight mating saws-by r ason .of the" filing ate-bab grind-mg.

of a grooving saw having its operating po'rtionlying suhstantlallyln alane alidso armngedas to' avoid the tendencyof thesaw' to fan the aimedthrow dust and chips. A

further object is to provide a saw Cap'ahleof being formed to producethe asird'wdb A st nts Hei-'ob"eet is e ithets-sew or this type Which isreadily; interohangealole fact that it requires ne spee si bevelled cal:

Ialsermsndre1st0 holdit in'c'orreet position on'itsspindle. Stillanotherobject isto rovides dado saw in wHieh-itishnnecesssry rosetfeteeth; Tothese and other endstheinventionire sides in eerta-inimproveinents andcoinbiriations of parts; all. as vvill be hereinafter more fully de's'erihed', the meter features being;

pointedflout in" the 'e'la'iins" at the end of the spetification. v-ntliserawings; Fig: 1* is an eleventh or a saw embodying my invention;V

" Figl verftieal seetion talr'en on line i tothfe spindle;

Fig: 3 is'a view similar to Fig; 1 showinga slightly modified form;

Fig; 4; a verti'c'al: se etio'njtaken' on line 43 4 of Fig. 3 Withtliesavv secured in'p'osit'iono'h its spindle by amodified forrn of atFig.5 isatmgi entary detail vlew of the edge of the saw showing themanner of relieviiigthe-teth.

Sirhilt r refereiioe nun iera ls throughout theseveral'vievvs"indioatethe'same parts},

Referrin'gto the drawings, 1 indicates initiated-saw having; teeth '2 onits p er'iphery assembly enthe head."

as providedwith f hearing opening 3 for Whichare used The saw ispreferably, butjnotnecessarily, constructed fro'ina relatively thickcirciilar disk and on each face ofthe disk I'fonn inclined eoncentrioinounting faces herein shown in the form of depressions 5; The deepestportion of the depression onone face of thesa'W lies opposite to theshallowest portion of the depression on the opposite face of the saw, sothat the material included between the depressions is substantially ofuniform thickness at all points. In practice the shallow'est poi'tionofthe depression may substantially coincide with the original face of thedisk, theparticularplace, however, vhere the plane of thedepression'interseets theplane of the disk is not iinportant. The

depressed portions -5 are preferably 1 formed by a grinding process, theparticular manner of grinding the depressions, however, is not n'tteri'al to the present invention.

' Itw'ill be seen that tllQlllOllIllllIlg Whiehis that part ofthe sawincluded between the depressed portions, issubstantially or uniformjthiekness and is inclined to the plane ofthe outer edge of the disk,

Thesaw ma be secured ona spindle 4 by portion,

nie'aiisof ahead 6 fiX edon the spindle. Them head 6' is provided withaoentering' ineniber 7 the saw. The flange? onthe headisfof a" s3-sizeto substantially lit within one of the depressed portions ofthe'saw.A collar 8 ei'lgages inthe opposite depressed portion of the saw fromthe flange M An additional coller 9 andvvasher lO arepl'aced on thespindle Contact With the' COlIar 8and all i a are heldtiiiplace by aznutll seeured on the threaded end of thespindle 4Q y The headhahlcollar 8,as shown, are the ordinary straight head and collar elements withordinary straiglit cutting saws. 1 7 It will i he noted that the teethand the pe: ri 'pheryflofthe saw disk lie in substantially a single planahd the mounting portion lies in another plane Whichjis inclined to theplane of the periphery and teeth; Therefore, when t the mountingportionis engaged between the straight head andc ollar meinbers onspindle 4, the plane of the teeth Willbe inclined away from a rightangular relation to said spindle, and when the saw is rotated by thespindle the periphery and teeth will have a wobbling action. It is thisarrangement that enables the teeth to cut a groove which is wider thantheir width.

In order to provide for the proper cutting action of the teeth and toavoid binding of the teeth in the work, each tooth is provided with arelieved or cut-away portion 13, on the side thereof toward which thetooth moves due to its wobbling action as the saw rotates. In practiceone half of the number of teeth of the saw are relieved on one side andthe remaining half of the teeth are relieved on the opposite side. Asshown in Fig. 1., the teeth from B to X going in a clockwise directionaround the saw are relieved on the front as illustrated. in full linesand the remainder of the teeth are relieved on the back as shown indotted lines.

An adjusting means may be provided for varying the inclination of thesaw with respect to the spindle 4. This adjusting means comprises aplurality of set screws 14, carried in the saw disk, four being shownfor pur poses of illustration, spaced equally around the center of thesaw. When it is desired to change the inclination of the saw to producea wider groove, the upper set screws 14 as shown in Fig. 2 are turned soas to project farther to the left and the lower set screws 14 are turnedso as to project farther to the right.

hen the collar 8 is again placed in position after the set screws havebeen adjusted, it will be seen that the ends of the upper set screwswill contact against the collar '7 and on the lower side of the shaftthe collar 7 will engage in the depressed portion on that side of thesaw. The collar 8 will engage the ends of set screws 14 below thespindle 4, and above the spindle the collar 8 will engage in the deepestportion of the depression in that face of the saw.

If it is desired to narrow the groove made by the saw, or even toconvert the saw for straight cutting, the set screws 14 will be "urnedto cause them to project in a direction reverse to that described above.It will )e seen that when the screws are thus adjusted, they willproject outwardly at the deepest part of the depressed portion on thecorresponding faces, so that they will align the saw between flange 7and collar 8 to a position more nearly at right angles to the spindle 4.

In the operation of my improved saw, let it be assumed that the saw isrotating in the direction of the arrow in Fig. 1. As the'saw wobbles inits rotation the tooth A will make a cut at one extreme side of thegroove and tooth X will make a corresponding cut at the other side. Thetooth B, following tooth A, will begin to cut back toward the other sideof the groove and each following tooth will cut farther toward the sameside until tooth Y comes into operation. Tooth Y will start to outtoward the opposite side and each following tooth from Y to A will cutfarther over toward this side until B again enters the work.

In the modification illustrated in Figs. 3 and 4, the saw 20 has teeth21 and depressed portions 22 which are identical respectively with teeth2 and depressed portions of Figsl and 2. In this form I provide adifferent means for adjustably mounting the saw with relation to spindle23 and head 24. The head 24 is secured on spindle 23 by means of a setscrew 24 and provided with a flange 25 and the centering extension 2%)similar to the construction shown in Fig. 1.. At spaced points aroundthe centering element the flange 25 has holes 27 therein for thereception of bolts 28. Holes 29 are provided in the depressed centralportion of saw 20. These holes register with holes 27, so that the sawmay be securely fixed on the head 24 by means of said bolts 28. Two setscrews 30 are screwed into the depressed portion 22, one being adjacenteach of the lower bolts 28 as seen in Fig. 1. These set screws areadapted to bear against the face of the head 24. By screwing the setscrews 30 in the direction of the head it will beseen that the loweredge of the saw, as seen in Fig. 4, will be moved to the right and thusthe groove which will be made by the saw 20 will be narrower. By movingthe set screws 30 until the plane of the saw teeth is coincident withthe plane of the face of the head 24 it is apparent that the saw canthen be used for straight cutting.

Fig. 5 shows the relieved sides of the teeth somewhat exaggerated forthe sake of clearness. The two teeth at the left in this figure are thelast of one series and the next two teeth are the first of the otherseries. t will be noted that the front edges of successive teeth arereversely inclined as shown at 2] and 21".

It will be observed that my improved saw requires no special inclinedheads, washers or the like, so that it will be freely interchangeablewith ordinary straight cutting saws.

The practice of forming an inclined surface on a saw by grinding ofiersseveral dis tinct advantages over prior constructions in which theinclined surface is produced by forming up or bending. Where suchbending or pressing is resorted to, relatively thin stock must be usedsince it is impracticable to bend relatively thick stock. The bendingcan rarely be performed without some distortion of the parts of the sawwhich should be straight. Also the bending tends to pro duce a conditionof internal stress upon the structure of the metal which in use of thesaw,

with the attendant heating due to friction,

3 fact that no pressing or bending is necessary and there is no tendencyto Warp since no internal stresses are produced in its manufacture. V

It will be noted further that a sawembodyin'g my improved constructionpresents no definlte radial pro ect1ons or shoulders and hence islargely freed fromthe fanning action, or, in other words, the tendencytocatch and throwair, dust and chips which is characteristic of saw disksformed up or pressed .to provide inclined portions with definiteshoulder pro ect1ons therebetween, or disks of segmentalshape, as insome prior constructions.

1 claim as my invention: 1. A dado saw comprising a ClICUlilldlSk havinga continuous series of peripheral teeth lying in a common plane, saiddisk havinga recessed portion affording a lateral mounting face lying ina plane inclined to the plane of said teeth.

vided with cutting teeth and having an inner mounting portion of lessthickness than said peripheral portion and inclined to the planethereof.

3. A dado saw comprising a disk having its periphery lying in a planeand provided with 7 cutting teeth and a lateral inner mounting faceground in said disk at an inclination to said peripheral plane. 3

4;. A dado saw comprising a circular disk having a continuous series ofperipheral teeth lying in a common plane and means for mounting saiddisk on aspindle with said plane inclined from a right angle relation tosaid spindle, said teeth being relieved from front to rear at the sidesthereof which are advanced laterally toward the Work by said inclinedmounting.

5. A dado saw comprising a disk having its peripheral portion lying in aplane and providedrwith cutting teeth, said disk having a lateralmounting face lying inwardly of the opposite faces of said peripheralportion and inclined thereto. 7 I V 6. A dado saw comprising a diskhaving a peripheral portion lying-in a plane and provided with cuttingteeth and having an intermediate portion recessed on its opposite sidesand inclined to the peripheral portion. 7. A dado saw comprising a diskhaving a peripheralportion lying in a plane, said portion being providedwith cutting teeth, said disk having an intermediate portionrecessed onits oppositesides and affording substantially parallel mounting faces,each of which an intermediate mounting is inclined to one face portion.

8. A dado saw comprising a disk having a of said peripheral peripheralportion provided with cutting.

teeth, said disk having an intermediate portion recessed on its oppositesides and inclined to the peripheral; portion, said inter mediateportionbeing of less thickness than said peripheral portion. I

9. A dado saw comprising a disk having, a 75 peripheral portion lying inaplane and provided with cutting teeth, said disk having a lateralmounting portionlying inwardly of the opposite faces of said peripheralportion and inclined thereto, a spindle for driving said disk having asupporting element therefor engaging one side of said mounting portion,a second supporting element engaging the opposite side of the mountingportion, and a plurality of devices adjustably connected with the diskfor varying its inclination relative to the axis of the spindle, certainof said devices being arranged for engagement with one of said elementsand the remaining devices with the opposite element when the disk is inapredetermined position V a of adjustment upon the spindle. 2. A dadosaw coin prising a disk having its peripheral portion lying in a planeand pro- 10. A dado saw comprising a disk having a peripheralportionlying in a plane and provided. with cutting teeth, said diskhaving portion in a plane inclined to the plane of said peripheralportion, a spindle for driving said saw having a supporting elementengaging one side of the mounting portion, a second supporting elementclamped upon the other side of said a mounting portion and a pluralityof set screws threaded within the saw disk and ad just-able to vary theinclination of the disk relative to the axis of the spindle, each ofsaid screws being mounted independently of one-of said supportingelements.

11. A'dado saw comprising a saw disk,supporting elements for the diskengaging opposite faces thereof, means for clamping said elements uponthe saw disk, separate and independent devices adjustably connected withthe disk for varying the inclination of the latter relative to its axisof rotation, certain of the devices being mounted independently of oneof said elements and arranged for engagement with the other and theremaining devices being mounted independently of the last mentionedelement and arranged for engagement with the other of said elements.WVARRE'N B. HUTHER.

